At the present time apparatus for shielding welds from atmospheric gas that include a second nozzle for the introduction of additional gas utilize the additional gas as a blast to clear the nozzle of spatter and debris after welding or concentric nozzles with the outer nozzle the source of a second more economical shielding gas to reduce the need for more expensive shielding gases used in the inner nozzle.
There is no teaching in the literature of the utilization of a second gas to shape the weld bead. The deflection of an arc presently is accomplished by the use of magnetic fields since the arc itself is an electrical current conductor. Magnetic fields are used to deflect an arc in a manner to improve welding performance. However, there is no disclosure in the literature of the use of gas pressure to deflect a welding arc forward in the direction of travel to increase welding speed and at the same time to shape the weld bead.